1. Field
Methods and devices consistent with the exemplary embodiments relate to a display apparatus, a power supply apparatus and a power supply method thereof, and more particularly, to minimizing wasteful power consumption generated in a discharging device which discharges a residual voltage when AC power stops being supplied.
2. Description of the Related Art
A display apparatus such as a TV or the like is equipped with a power supply unit, for example, a switched-mode power supply (SMPS), for supplying operation power. Such a power supply unit converts commercial utility AC power into operation power of different levels required for various components of the display apparatus.
A typical power supply unit includes circuit elements, for example, capacitors used for AC filtering, which are charged with a considerable voltage in normal operation. Accordingly, in order to prevent a user from being electrically shocked by the charged voltage (hereinafter also referred to as “residual voltage”), when the user unplugs a power cord, the power supply unit is provided with a discharging resistor for discharging the residual voltage.
However, in the related art, since such a discharging resistor is constantly connected in the power supply unit, a discharged current may flow through the discharging resistor not only when the discharging resistor protects the user who unplugs the power cord, but also when the AC power is normally supplied to the components of the display apparatus, which may result in wasteful power consumption.
More particularly, the AC power is supplied to the power supply unit even when the display apparatus is in a standby mode to minimize power consumption. Since the display apparatus is not normally operated in the standby mode, a significant amount of power is wasted.
Such wasteful power consumption caused by the discharging resistor may occur in not only the display apparatus but also various forms of electronic devices with the above-mentioned power configuration.